No. Once Google revokes an old version of the CDM, the servers will refuse to issue a license for that version. The license basically contains encrypted keys fo

No. Once Google revokes an old version of the CDM, the servers will refuse to issue a license for that version. The license basically contains encrypted keys for the content. If you already saved the decrypted keys for a specific content, you will be able to decrypt it even after the revocation, but you won't be able to get the keys for any new content with that version anymore. We're not (yet) at the point where actual content keys are rotated frequently, because that sounds like a lot of effort though technologies exist for this already, they're just not in widespread use.